Παιδιατρική | Τόμος 67 • Τεύχος 2 • Μάρτιος - Απρίλιος 2004

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¶·È‰È·ÙÚÈ΋ 2004;67:75-87

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Paediatriki 2004;67:75-87

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∆Ô Ï›Ô˜ ÙÔ˘ ÛÒÌ·ÙÔ˜: ¤Ó·˜ ÂÓ‰ÔÎÚÈÓ‹˜ ·‰¤Ó·˜ ∫. ¶·ÓÙÛÈÒÙÔ˘

Adipose tissue: an endocrine organ K. Pantsiotou

¶ÂÚ›ÏË„Ë: ∆Ô Ï›Ô˜ ·ÔÙÂÏ› ÙËÓ ·ÔıËÎÂ˘Ì¤ÓË ÂÓ¤ÚÁÂÈ· ÙÔ˘ ÛÒÌ·ÙÔ˜, ÂÓÒ Ë ÌÂÁ·Ï‡ÙÂÚË ÔÛfiÙËÙ· (50%) ‚Ú›ÛÎÂÙ·È ˘Ô‰ÔÚ›ˆ˜. ∏ ·Ó·ÏÔÁ›· ÙÔ˘ ÛÒÌ·ÙÔ˜ Û ϛÔ˜ ·˘Í¿ÓÂÙ·È ÛËÌ·ÓÙÈο ·fi ÙË Á¤ÓÓËÛË ¤ˆ˜ ÙÔ ÚÒÙÔ ¤ÙÔ˜ Ù˘ ËÏÈΛ·˜, ÂÏ·ÙÙÒÓÂÙ·È ¤ˆ˜ ÙÔ 4Ô ¤ÙÔ˜ Î·È ÌÂÙ¿ ·˘Í¿ÓÂÙ·È, ·˘Í·ÓÔÌ¤ÓˆÓ ÙÔ˘ ‚¿ÚÔ˘˜ Î·È Ù˘ ËÏÈΛ·˜, ̤¯ÚÈ ÙËÓ 6Ë-7Ë ‰ÂηÂÙ›· Ù˘ ˙ˆ‹˜ (ÛÙȘ Á˘Ó·›Î˜ ÂÚÈÛÛfiÙÂÚÔ). ∫·Ù¿ ÙËÓ ÂÊ˂›·, ÂÈÙ·¯‡ÓÂÙ·È Ë ·‡ÍËÛË ÙÔ˘ Ï›Ô˘˜ ÛÙȘ ı‹ÏÂȘ Î·È ÂÏ·ÙÙÒÓÂÙ·È ÛÙÔ˘˜ ¿ÚÚÂÓ˜. ∏ ·¯˘Û·ÚΛ· ·ÔÙÂÏ› ÙÔ Û˘¯ÓfiÙÂÚÔ ÔÏ˘ÁÔÓȉȷÎfi ÎÏËÚÔÓÔÌÔ‡ÌÂÓÔ ÓfiÛËÌ·, ÏfiÁˆ ·Ôı‹Î¢Û˘ Î·È ÌË Î·‡Û˘ Ù˘ ÂÈϤÔÓ ÙÚÔÊ‹˜, ·ÏÏ¿ Î·È ÏfiÁˆ ·˘ÍË̤Ó˘ ηٷӿψÛ˘. ∞fi ÙÔ˘˜ ÏÈÌÔ‡˜, ·Ó¿ ÙÔ˘˜ ·ÈÒÓ˜, Â¤˙ËÛ·Ó ¿ÙÔÌ· Ô˘ ·ÍÈÔÔÈÔ‡Û·Ó Î·Ï‡ÙÂÚ· ÙËÓ ÙÚÔÊ‹ ÙÔ˘˜ ‹ ›¯·Ó ÂÚÈÛÛfiÙÂÚ· ·Ôı¤Ì·Ù· ÂÓ¤ÚÁÂÈ·˜. ∂ÓÙÔ‡ÙÔȘ, Û ÂÚÈfi‰Ô˘˜ Ì ·ÊıÔÓ›· ÙÚÔʛ̈Ó, ÔÈ ·fiÁÔÓÔÈ ·˘ÙÒÓ ÙˆÓ ·ÙfiÌˆÓ ·ÚÔ˘ÛÈ¿˙Ô˘Ó ·¯˘Û·ÚΛ·. O ÏÈ҉˘ ÈÛÙfi˜ Û¯ËÌ·Ù›˙ÂÙ·È ÁÈ· ÙËÓ ·Ôı‹Î¢ÛË ÂÓ¤ÚÁÂÈ·˜, Ë ÔÔ›· ÂÍÔÈÎÔÓÔÌÂ›Ù·È fiÙ·Ó ÏÂÔÓ¿˙ÂÈ Ë ÙÚÔÊ‹, ÂÓÒ Î·Ù·Ó·ÏÒÓÂÙ·È fiÙ·Ó ‰ÂÓ ˘¿Ú¯ÂÈ ÙÚÔÊ‹ ÛÙÔ ÂÚÈ‚¿ÏÏÔÓ. ŸÙ·Ó ·ÊıÔÓ› Ë ÙÚÔÊ‹, Û˘ÛÛˆÚ‡ÂÙ·È Ï›Ô˜ ¤Ú·Ó ÙˆÓ ·ÓÒÙÂÚˆÓ Ê˘ÛÈÔÏÔÁÈÎÒÓ ÔÚ›ˆÓ, ·ÏÏ¿ Ô ÔÚÁ·ÓÈÛÌfi˜ ·ÓÙÈÛÙ¤ÎÂÙ·È Ì ÙÔ ÌÂÙ·‚ÔÏÈÎfi Û‡Ó‰ÚÔÌÔ, ÂÓÒ Ë ÈÓÛÔ˘Ï›ÓË Î·È ÔÈ ·˘ÍËÙÈÎÔ› ·Ú¿ÁÔÓÙ˜ (IGF-πs, ·ÁÁÂÈÔÙÂÓÛÈÓÔÁfiÓÔ ππ, TGFs) ·˘Í¿ÓÔ˘Ó ÙË ÏÈÔÁ¤ÓÂÛË ÛÂ Û˘ÓÂÚÁ·Û›· Ì ÙÔ˘˜ ÂÓÂÚÁÔÔÈË̤ÓÔ˘˜ ˘ԉԯ›˜ ÙˆÓ ÔÏÏ·Ï·ÛÈ·ÛÙÒÓ ÙˆÓ ˘ÂÚÔÍ˘ÛˆÌ¿ÙˆÓ (PPARÁs) Î·È ÙÔ˘˜ ÌÂÙ·ÁÚ·ÊÈÎÔ‡˜ ·Ú¿ÁÔÓÙ˜ (C/EBP, SREP). ∞fi ÙÔ ·˘ÍË̤ÓÔ Ï›Ô˜ ÂÎÎÚ›ÓÂÙ·È ÂÚÈÛÛfiÙÂÚË ÏÂÙ›ÓË, Ô˘ ÏËÚÔÊÔÚ› ÙÔÓ ˘Ôı¿Ï·ÌÔ (ΤÓÙÚÔ ÎÔÚÂÛÌÔ‡) fiÙÈ ˘¿Ú¯ÂÈ Â¿ÚÎÂÈ· ÂÓ¤ÚÁÂÈ·˜ ÁÈ· ‰È·Ù‹ÚËÛË Ù˘ ÔÌÔÈÔÛÙ·Û›·˜ ÙÔ˘ ÛÒÌ·ÙÔ˜ ¯ˆÚ›˜ ÙË Ï‹„Ë ÙÚÔÊ‹˜, ·˘Í¿ÓÔÓÙ·È ÔÈ Î·‡ÛÂȘ, ‰È·ÙËÚÂ›Ù·È Ô ÌËÓÈ·›Ô˜ ·ÎÏÔ˜

Abstract: Adipose tissue is the energy store of the body and about 50% of it is subcutaneous. The proportion of body fat increases from birth to one year, decreases up to the age of 4 years, then increases again as weight is gained, continuing until the 6th-7th decades of life, and a little longer in females. During puberty the adipose tissue increases in girls and decreases in boys. Obesity is the most common polygenetically inherited disease, caused by excess consumption of food and storage of energy. In earlier times when people had to survive famines they made better use of their food and deposited more as fuel. Later, with an excess of food, their descendants started to become obese. Adipose tissue was evolved to cope with limited energy in the environment by storing energy, but it has not evolved further to homeostasis in periods of abundance of food. In the case of increased ingestion of food for a long period, the adipose tissue resists with poor adaptation (metabolic syndrome). When there is plenty of food the insulin and growth factors (IGF1s, angiotensinogen II, TGFs) signal growth in fat, in conjunction with peroxisome proliferator activated receptors (PPARs) and transforming factors (C/EBP, SREBP). In normal circumstances increased fat produces more leptin which informs the centre of satiety in the hypothalamus that there is sufficient energy to preserve homeostasis without food consumption, combustion is increased, puberty is signalled in children, the menstrual cycle is preserved in girls and fat deposition is decreased to low normal. The adipose tissue covers the body and is in touch with environmental stimuli and signals factors that cause apoptosis of affected cells. The adipose tissue resists its own growth by

∂Ó‰ÔÎÚÈÓÔÏfiÁÔ˜

Endocrinologist

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